a genus of grasses. They are perennials with a panicled (less commonly spike-shaped) inflorescence with numerous spikelets. The spikelets are monanthous; the axis of the spikelet has hairs that impart a downiness to the entire inflorescence at the time of ripening. There are about 100 species (according to other data, more than 200), mainly in the cold and temperate zones, as well as in mountains and tropical zones of both hemispheres. About 50 species exist in the USSR; the most common (under a great variety of conditions) is wood reed bent (C. epigeios), which often grows in cleared areas in forests and prevents regeneration. Calamagrostis arundinacea grows in forests and thickets; purple reed bent (C. canescens), on swampy floodplain meadows; C. neglecta, in peat and sedge bogs and swampy meadows; and purple pine-grass or rough blue-joint (C. purpureus; formerly C. langsdorfii), in river valleys, swamps, wet scrub, and grass plots in forests, especially in Eastern Siberia and the Far East.